• Title/Summary/Keyword: wet-dry

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The Study on Soil Classification in Sri Lanka

  • Hyun, Byung-Keun;Mapa, R.B.;Sonn, Yeon-Kyu;Cho, Hyun-Jun;Shin, Kooksik;Choi, Jung-won;Jung, Seog-Jae;Jang, Byung-Chun
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.3
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    • pp.153-162
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    • 2015
  • Land information is important for the international agricultural companies. This study investigated the agriculture and soil information in Sri Lanka. This study is the results from investigation of soil properties and agricultural properties determined by the Soil Taxonomy classification system for the soils in Sri Lanka. The order of the main agricultural imports in Sri Lanka was wheat > refined Sugar > dry Onion > Rice > Lentils. The climate of Sri Lanka is divided into three climatic zones. There are a wet zone, an intermediate zone, and a dry zone. Rainfall of the wet zone was $3,000-5,000mm\;year^{-1}$. The rainfall of the dry zone was less than $1,000m^{-1}$. The intermediate zone was in the middle area. Soil series of Sri Lanka were 109 in total. Detailed information of soil series was: 6 of soil Orders, 15 of Suborders, 39 of Great groups, and 56 of Subgroups. Soil texture of topsoil was much more coarse, but subsoil was gravelly coarse soil. Soil of Sri Lanka was classified as a Soil Order. The orders were Entisols > Alfisols > Ultisols > Inceptisols > Histosols > Vertisols.

Manufacturing of Multi-Layer Coated Paper with Eco-Friendly Bio-Binder for Cost Saving (1) - Application for Pre-Coating Layer - (친환경 원가 절감형 바이오바인더를 이용한 다층 도공지 제조(제1보) - Pre-coating층에 대한 적용 -)

  • An, Guk Heon;Choi, Ki Soon;Won, Jong Myoung;Lee, Yong Kyu
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.6
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    • pp.63-70
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    • 2014
  • Part of SB latex in pre-coating color was substituted with newly developed starch-based bio-binder in order to investigate the effect of starch-based bio-binder in pre-coating color on the properties of coating color and coated paper. Smoothness and gloss of coated paper were decreased with the increase of bio-binder substitution ratio. Brightness and whiteness did not show the significant changes, but stiffness was improved with bio-binder. Ink set-off, dry-pick and wet pick were decreased with the increase of bio-binder substitution ratio. In general, when all SB latex is substituted with bio-binder, ink set-off, dry- and wet-pick were deteriorated. However, it was found that if the bio-binder substitution ratio is controlled below 50%, similar qualities with coated paper manufactured by the use of SB latex binder can be obtained.

Monitoring of Dry Cutting and Applications of Cutting Fluid for Ball End Milling

  • Tangjitsitcharoen, Somkiat;Rungruang, Channarong;Laiaddee, Duangta
    • Industrial Engineering and Management Systems
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    • v.9 no.3
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    • pp.242-250
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    • 2010
  • For economical and environmental reasons, the aim of this research is hence to monitor the cutting conditions with the dry cutting, the wet cutting, and the mist cutting to obtain the proper cutting condition for the plain carbon steel with the ball end milling based on the consideration of the surface roughness of the machined parts, the life of the cutting tools, the use of the cutting fluids, the density of the particles of cutting fluids dispersed in the working area, and the cost of cutting. The experimentally obtained results of the relation between tool wear and surface roughness, the relation between tool wear and cutting force, and the relation between cutting force and surface roughness are correspondent with the same trend. The phenomena of surface roughness and tool wear can be explained by the in-process cutting forces. The models of the tool wear with the cutting conditions and the cutting times are proposed to estimate the tool cost for the different cooling strategies based on the experimental data using the multiple regression technique. The cutting cost is calculated from the costs of cutting tool and cutting fluid. The mist cutting gives the lowest cutting cost as compared to others. The experimentally obtained proper cutting condition is determined based on the experimental results referring to the criteria.

A Study on the Physical Properties of Recycled Fine Aggregate (by Dry and Wet Type Production formula) Mortar Using Blast Furnace Slag (고로슬래그를 사용한 건식 및 습식 재생 잔골재 모르타르의 물리적 특성에 관한 연구)

  • Shim, Jong-Woo;Lee, Sea-Hyun;Seo, Chi-Ho
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.501-504
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    • 2006
  • Recycled aggregate mortar contains plenty of calcium hydroxide to improve the strength of blast furnace slag, although the surface mortar made of recycled aggregate deteriorates adhesion to cement paste and blast furnace slag has a low initial strength. Therefore, this study assumes that the combination with both recycled aggregate and blast furnace slag will produce a better performance. The results of the experiment show that dry mortar made of recycled aggregate provides with higher strength than wet mortar does at the 3-day and 7-day age, while lower at the 28-day age. It indicates that a large amount of cement mortar made of dry recycled aggregate has deteriorated adhesion strength. The mixes with 30% and 50% of blast furnace slag and 50% and 75% of recycled aggregate provide with much better strength at the 7-day age, although they usually have latent hydraulic property at the 28-day age. It indicates that calcium hydroxide($Ca(OH){_2}$) in recycled aggregate has affected ground granulated blast furnace slag.

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Comparison of Pollutant Control in Combined Sewer Overflows and Separated Sewer Overflows using the Separation Wall (우오수분리벽을 이용한 합류식 하수관거와 분류식 우수관거의 월류수 제어효과 비교)

  • Lim, Bong-Su;Kim, Do-Young;Lee, Kuang-Chun
    • Journal of Korean Society on Water Environment
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    • v.23 no.4
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    • pp.458-466
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    • 2007
  • This study is to evaluate control effects of separation wall by surveying water quality and sewer overflows during dry and wet periods in combined sewer and separated sewer systems. Ravine water from the combined Seokgyo outfall with the separation wall was separated about four times larger than sewage flow during dry periods. The water quality of the combined Seokgyo outfall with separation wall during dry periods is flow weighed average BOD 61 mg/L, the combined Cheonseokgyo outfall without the separation wall is average BOD 71 mg/L, and the separated Pyeongsong center outfall is average BOD 41 mg/L. The BOD concentration in separated outfall form about 57% of the combined outfall, and this means the separated outfall (i.e. storm sewer) is polluted by inflow of sewage. The overflow load of the separated outfall is ten times higher than the combined outfall and its overflow load per rainfall is three times than combined outfall during the wet periods. Therefore, the control plan of overflow load is required in storm sewer. The control effects of the overflow load increased 79% by setting the separation wall in the combined sewer, and showed 27% increase without the separation wall in separated sewer, but forecasted over 80% increase of effects if the separation wall was set.

Evaluation on Resistance to Pitting Corrosion of Fe-Cr Alloys via Measurement of the Critical Pitting Temperature (CPT) and Potentiodynamic Polarization According to KS D 0238 (wet, dry), ASTM G 61 and ISO 17475 Standards (Fe-Cr합금의 공식저항성 평가를 위하여 다양한 규격(KS D 0238, ASTM G 61, ISO 17475)에 따라 실시한 동전위 분극 시험과 임계공식온도 측정시험)

  • Kang, Su-Yeon;Lee, Jae-Bong;Kim, Yeong-Ho
    • Korean Journal of Metals and Materials
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    • v.47 no.10
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    • pp.635-643
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    • 2009
  • The resistance to pitting corrosion of Fe-Cr alloys was evaluated by performing potentiodynamic polarization and critical pitting temperature (CPT) tests. For the potentiodynamic polarization tests, various standards were applied, i.e., KS D 0238 (wet, dry), ASTM G 61, and ISO 17475, showing different potentiodynamic polarization results including pitting potentials. ASTM G 61 and ISO 17475 standards presented relatively higher pitting potential while KS D 0238 (dry) indicated lower values than the others. Effects of surface roughness, scan rates, and exposure time to air before tests were also investigated. CPT tests were performed under two different applied potentials, 300 m$V_{SCE}$ and 200 m$V_{SCE}$ in deaerated 1 M NaCl aqueous solution. CPT values and the polarization test results showed a linear relationship.

Mechanical Device Design for Solvent Usage Reduction for Amine Group Substitution and Production of NH2-HNT (아민기 치환 시 용매 사용량 절감을 위한 기계 장치 설계 및 NH2-HNT 제조)

  • Moon il Kim
    • Journal of Environmental Science International
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    • v.32 no.6
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    • pp.477-482
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    • 2023
  • Halloysite nanotube (HNT) has a nanotube structure with the chemical formula of Al2Si2O5(OH)4 · nH2O and is a natural sediment of aluminosilicate. A lot of research has been conducted to improve the mechanical properties of epoxy composites by generating interactions between HNTs and polymers through surface treatment of HNTs, such as exchange of amine group as a terminal functional group. However, most of the surface modification methods are performed under wet conditions, which require a relatively large amount of time, manpower and solvent. In order to save time and simplify complicated procedures, a dry coating machine was designed and used for amine group exchange. Comparing the XPS results, it was found that the results of NH2-HNT prepared using a dry coating machine and the substitution through the wet method were not significantly different, and it has been confirmed that the amount of solvent used and the time savings can be made.

A Study on Fundamental Performance of Epoxy Resin Mortar Mixed Special Cement for Concrete Surface Control (특수시멘트 혼입 에폭시 수지계 콘크리트용 바탕조정재의 기초물성에 관한연구)

  • 최성민;김용현;황원주;오상근
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10c
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    • pp.145-150
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    • 1998
  • This study deals with the effect on performance of epoxy resign mortar mixed special cement for surface control and maintenance of aging concrete construction. The test of main property of epoxy resign in this study are the evaluation on the adhesive strength between substrate and epoxy resign mortar under the environment of wet or concrete substrate surface. We gained the test results of good adhesive strength over 15 kgf/$\textrm{cm}^2$ under the wet and dry condition of concrete surface.

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A Study on Estimation of Wet Deposition Flux using ADOM (ADOM을 이용한 습성침적 플럭스 산정에 관한 연구)

  • 이화운;문난경;임주연
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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    • pp.87-88
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    • 2001
  • 대기오염물질 제거에 중요한 역할을 하는 침적 현상은 크게 건성침적(dry deposition)과 습성침적(wet deposition)으로 구분된다. 건성침적은 오염물질이 중력이나 분자 확산에 의해 지면이나 그 부근에 침강ㆍ흡착하는 현상이며, 습성침적은 구름 속의 에어로졸이 응결핵으로 제거되는 성우제거(rainout)와 구름 이하의 고도에서 강수에 의해 제거되는 세척제거(washout)와 같은 현상을 일컫는다. 습성침적은 강수 및 구름 물리와 관련하여 대기 중 오염물질 제거에 큰 비중을 차지함에도 불구하고 건성침적에 비해 그 연구가 미흡한 실정이며, 침적 모형을 이용한 연구는 더욱 찾아보기 어렵다. (중략)

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Partially Dry-Transferred Graphene Electrode with Zinc Oxide Nanopowder and Its Application on Organic Solar Cells (ZnO 나노 분말 코팅 기반 건식전사 그래핀 전극 제작 및 유기태양전지 응용)

  • Jo, Yeongsu;Woo, Chae Young;Hong, Soon Kyu;Lee, Hyung Woo
    • Journal of Powder Materials
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    • v.27 no.4
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    • pp.305-310
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    • 2020
  • In this study, partially dry transfer is investigated to solve the problem of fully dry transfer. Partially dry transfer is a method in which multiple layers of graphene are dry-transferred over a wet-transferred graphene layer. At a wavelength of 550 nm, the transmittance of the partially dry-transferred graphene is seen to be about 3% higher for each layer than that of the fully dry-transferred graphene. Furthermore, the sheet resistance of the partially dry-transferred graphene is relatively lower than that of the fully dry-transferred graphene, with the minimum sheet resistance being 179 Ω/sq. In addition, the fully dry-transferred graphene is easily damaged during the solution process, so that the performance of the organic photovoltaics (OPV) does not occur. In contrast, the best efficiency achievable for OPV using the partially dry-transferred graphene is 2.37% for 4 layers.